Answer:
ΔH°rxn = -827.5 kJ
Explanation:
Let's consider the following balanced equation.
2 PbS(s) + 3 O₂(g) → 2 PbO(s) + 2 SO₂(g)
We can calculate the standard enthalpy of reaction (ΔH°rxn) from the standard enthalpies of formation (ΔH°f) using the following expression.
ΔH°rxn = [2 mol × ΔH°f(PbO(s)) + 2 mol × ΔH°f(SO₂(g)
)] - [2 mol × ΔH°f(PbS(s)) + 3 mol × ΔH°f(O₂(g)
)]
ΔH°rxn = [2 mol × ΔH°f(PbO(s)) + 2 mol × ΔH°f(SO₂(g)
)] - [2 mol × ΔH°f(PbS(s)) + 3 mol × ΔH°f(O₂(g)
)]
ΔH°rxn = [2 mol × (-217.32 kJ/mol) + 2 mol × (-296.83)] - [2 mol × (-100.4) + 3 mol × 0 kJ/mol]
ΔH°rxn = -827.5 kJ
The first one is right and so is eight you have to add them together to see if they go together if they dont add what is missing
The volume of the soft drink solution in milliliters that contains 102.5 g of sucrose is 11.93mL.
<h3>How to calculate volume?</h3>
The volume of a solution can be calculated by dividing the mass by the density. That is;
Volume = mass/density
According to this question, a soft drink contains 12.1% sucrose (C12H22O11) by mass. This means that the mass of the sucrose is
12.1/100 × 102.5 = 12.40g of sucrose
Volume = 12.40g ÷ 1.04g/mL
Volume = 11.93mL
Therefore, the volume of the soft drink solution in milliliters that contains 102.5 g of sucrose is 11.93mL.
Learn more about volume at: brainly.com/question/1578538
<u>Answer:</u> The final temperature of the coffee is 43.9°C
<u>Explanation:</u>
To calculate the final temperature, we use the equation:
where,
q = heat released = 
m = mass of water = 10.0 grams
C = specific heat capacity of water = 4.184 J/g°C
= final temperature = ?
= initial temperature = 20°C
Putting values in above equation, we get:
Hence, the final temperature of the coffee is 43.9°C
